Semiconductor device having a heat-sink attached thereto

Abstract

A heat-sink is attached to a hermetic seal package of a face-up type semiconductor device such that a concavity is formed between the cap of the package and the heat-sink. Small holes using a vent are formed in the heat-sink between the concavity and the outside face of the heat-sink so as to communicate atmosphere outside the heat-sink to the concavity.

What is claimed is: 
     
       1. A semiconductor device comprising: a pedestal body of a package including a first planar surface at one side of said pedestal body, a second planar surface at another side of said pedestal body which is opposite to said first planar surface, and a recess formed at a center part of said one side of said pedestal body, said recess being depressed from said first planar surface and surrounded by first planar surface, said first planar surface having an inner section near said recess and surrounding said recess, and an outer section remoter from said recess via said inner section and surrounding said inner section;   a semiconductor element installed in said recess of said pedestal body;   a cap of said package bonded to said inner section of said first planar surface of said pedestal body to hermetically seal said recess;   resin;   a heat-sink including a planar surface at one side, a concavity formed at one side, said concavity being depressed from said planar surface and surrounded by said planar surface, said planar surface of said heat-sink being bonded to said outer section of said first planar surface of said pedestal body by said resin such that an enclosed space is formed by said concavity of said heat-sink and said package including said cap and   a plurality of small holes penetrating a member of said heat-sink constituting said concavity and reaching said concavity so that said small holes communicate between an atmosphere outside said heat-sink and said enclosed space constituted of said concavity of said heat-sink and said package including said cap.   
     
     
       2. A semiconductor device of claim 1, in which the side wall of said small hole is entirely made of said member of said heat-sink. 
     
     
       3. A semiconductor device of claim 2, in which said small hole has a diameter ranging from 1.5 mm to 3.0 mm 
     
     
       4. A semiconductor device of claim 1, in which the side wall of said small hole is made of said member of said heat-sink and of said resin. 
     
     
       5. A semiconductor device of claim 4, in which said small hole has a width in a direction in parallel with said planar surface of said heat-sink ranging from 1.5 mm to 3.0 mm. 
     
     
       6. A semiconductor device of claim 1, in which a number of said small holes is two or more and six or less. 
     
     
       7. A semiconductor device of claim 1, in which said resin is silicone resin. 
     
     
       8. A semiconductor device of claim 1, in which said heat-sink is made of aluminum or aluminum series alloy. 
     
     
       9. A semiconductor device of claim 1, in which said pedestal body is made of ceramic. 
     
     
       10. A semiconductor device of claim 9, in which ceramic is alumina.